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Choose your climateBased on winter hardiness only.

Annual · Asteraceae family

Bachelor's button

Centaurea cyanus

Full sun to part shade 11¾ in–2 ft 11⅜ in × 11¾ in–1 ft 11⅝ in Flowers May–July Demanding
Flower colors Click a color

In short a 10-second read

SunFull sun to part shade
Size11¾ in–2 ft 11⅜ in
spacing 9¾ in
FlowersMay–July
Care levelDemanding

Where to plant and how much to water

Sun, soil and water.

It grows best in full sun to part shade, in dry to average soil.

Sun

Sun6 hours or more
Part shade3–6 hours
Shadeunder 3 h

Soil

tolerates any pH
acidicneutralalkaline
dry to averageloamysandy

Watering

only in dry spellsdrought tolerant once establishedless when it rains

How much space it takes

Mature size.

The mature plant next to a person (69 in).

19¾ in3 ft 3⅜ in4 ft 11 in11¾ in–2 ft 11⅜ inspread 11¾ in–1 ft 11⅝ in
11¾ in–2 ft 11⅜ in× spread 11¾ in–1 ft 11⅝ in

Plant 9¾ in apart.

The final size depends on the cultivar and the spot — we give the range from smallest to largest.

Calendar

Through the year.

Typical for a temperate climate (four seasons). The line shows the current month.

The year at a glance

Flowers: JanuaryFlowers: FebruaryFlowers: MarchFlowers: AprilFlowers: MayFlowers: JuneFlowers: JulyFlowers: AugustFlowers: SeptemberFlowers: OctoberFlowers: NovemberFlowers: DecemberSowing: JanuarySowing: FebruarySowing: MarchSowing: AprilSowing: MaySowing: JuneSowing: JulySowing: AugustSowing: SeptemberSowing: OctoberSowing: NovemberSowing: DecemberFeeding: JanuaryFeeding: FebruaryFeeding: MarchFeeding: AprilFeeding: MayFeeding: JuneFeeding: JulyFeeding: AugustFeeding: SeptemberFeeding: OctoberFeeding: NovemberFeeding: DecemberJanFebMarAprMayJunJulAugSepOctNovDec
FlowersSowingFeeding
Now, in October: nothing to do — the next job is in March.
JanFebMarAprMayJunJulAugSepOctNovDec

Flowers

JanFebMarAprMayJunJulAugSepOctNovDec

May–July · blue, pink or white

Sowing

JanFebMarAprMayJunJulAugSepOctNovDec

direct sowing: March–May

Feeding

JanFebMarAprMayJunJulAugSepOctNovDec

April–May

Feeding

Nutrition.

Horn meal

up to 0.29 oz/sq ft a year, if the soil needs it · April–May

JanFebMarAprMayJunJulAugSepOctNovDec

Pests and diseases

Common problems and what to do.

The most common problems in Central Europe. Protection is listed from the gentlest option.

What you will see

White powdery coating on leaves, stems and flowers; leaves may become distorted.

When to look

From spring onwards

How to protect

  1. Prevention
    • Destroy fallen infected leaves in fall; do not over-feed, and protect from drought (stress invites powdery mildew).
  2. By hand fallPrune out infected shoots early and destroy fallen leaves.
Powdery mildewsdisease · from spring onwards

What you will see

White powdery coating on leaves, stems and flowers; leaves may become distorted.

When to look

From spring onwards

How to protect

  1. Prevention
    • Destroy fallen infected leaves in fall; do not over-feed, and protect from drought (stress invites powdery mildew).
  2. By hand fallPrune out infected shoots early and destroy fallen leaves.
More about this problem
Sources (2)

Frequently asked

Quick answers.

When does bachelor's button flower?

In May–July; the flowers are blue, pink or white.

When do I sow bachelor's button?

In March–May (direct sowing).

Does bachelor's button tolerate shade?

It tolerates part shade (3–6 hours of sun), but not full shade.

How much space does bachelor's button need?

At maturity 11¾ in–1 ft 11⅝ in wide and 11¾ in–2 ft 11⅜ in tall; recommended spacing 9¾ in.

Powdery mildews — what can you do?

Destroy fallen infected leaves in fall; do not over-feed, and protect from drought (stress invites powdery mildew). Prune out infected shoots early and destroy fallen leaves.

Sources (16) Checked 24 October 2026

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common yarrow

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Low maintenanceperennial
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